The Evolution of Soil Properties as it Relates to the Genesis of Volcanic Ash Soils in Costa Rica

Abstract

AbstractFive soil profiles developed on andesitic volcanic ash, under welldrained conditions and at various elevations associated with different climatic conditions, were studied.These soils varied in profile development and degree of weathering from Incipient Ando soil (Umbric Vitrandept), Mature Ando soil (Typic Dystrandept), and Senile Ando soil (Hydric Dystrandept) to Incipient Latosol (Typic Humitropept) and Mature Latosol (Typic Palehumult).Profile development associated with time of ash deposition and climate and recognized by virtue of morphological properties was closely related to progressive weathering and a consistent evolution of physical, chemical, and mineralogical properties, as well as to an increasing degradation of the native soil fertility.This investigation served as a basis for developing a working hypothesis on the genesis of volcanic ash soils from Regosols and Ando soils to Latosols.